IGCSE Biology 5 Views 1 Answers
Investigate, using a suitable stain, the pathway of water through the above-ground parts of a plant
Investigate, using a suitable stain, the pathway of water through the above-ground parts of a plant
Answered step-by-step
To investigate the pathway of water through the above-ground parts of a plant using a suitable stain, you can follow a systematic approach that highlights the movement of water from the roots to the leaves. Here’s a detailed outline based on the search results:
Investigation Outline
- Objective:
- To visualize and trace the pathway of water as it moves through the root hair cells, root cortex cells, xylem, and into the mesophyll cells of leaves.
- Materials Needed:
- Fresh cut stems of a herbaceous plant (e.g., carnation or celery).
- Food coloring or dye solutions (e.g., Brilliant Blue FCF or Toluidine Blue O).
- Water.
- Beakers or test tubes for dye solutions.
- Razor blade or scalpel for cutting stems.
- Clamp and ring stand for supporting stems.
- Microscope for observing stained sections.
- Method:
- Preparation:
- Cut the stem of a fresh herbaceous plant under water to prevent air from entering the xylem.
- Trim the cut end to expose fresh tissue.
- Dye Uptake:
- Place the cut end of the stem into a beaker containing a dye solution. Ensure that only the cut end is submerged.
- Allow the dye to be absorbed through the xylem for a set period (e.g., 30 minutes to 1 hour). During this time, water containing dye will move up through the xylem due to transpiration pull and capillary action.
- Observation:
- After sufficient time has passed, remove the stem from the dye solution and cut cross-sections of the stem at various heights using a razor blade.
- Observe these sections under a microscope to identify where the dye has moved within the xylem and other tissues.
- Preparation:
- Expected Results:
- The dye should be visible in the xylem vessels, indicating the pathway of water transport from roots through stems to leaves.
- You may also observe some dye in mesophyll cells if you allow enough time for water to move into leaf tissues.
- Analysis:
- Document and photograph stained sections to analyze how effectively water moves through different parts of the plant.
- Discuss how factors such as transpiration rate, humidity, and temperature might influence dye uptake and movement.
Did this page help you?